In a cluster shared disk architecture, all servers in a cluster share a storage. Generally, servers in a cluster may be classified into processing nodes and coordinator nodes according to functions. Generally, there are multiple processing nodes, which are configured to execute specific functions, for example, execute a specific structured query language (SQL) program and a specific transaction. When database performance needs to be improved, an overall cluster computing capability may be improved by adding a processing node for horizontal scaling. In addition, all processing nodes are mutually redundant, so that a failure of a single processing node does not affect another processing node. Generally, there is only one coordinator node, which is configured to coordinate a contended common resource during concurrent execution of multiple processing nodes.
An existing typical example of the cluster shared disk architecture is an Oracle® Real Application Clusters (RAC) solution. In that solution, processing nodes are directly interconnected by using a high-speed private network. Resources on all the processing nodes may be mutually shared and accessed. Concurrence is controlled by using a data manipulation language (DML) mechanism. The DML mechanism refers to a data lock, and is used to protect data integrity. A coordinator node in an existing technical solution (for example, Oracle® RAC) mainly implements coordination of a common resource contended by different nodes, without consideration of sharing of storage space on the coordinator node. Consequently, in a read-only or read-more-write-less scenario, data cached by a coordinator node is extremely limited. As a result, storage space on the coordinator node and a high-speed communication feature of InfiniBand® (a communication interface between the coordinator node and a processing node) cannot be fully used. This is a waste. In this way, in a scenario such as restarting of a processing node after a failure, or addition of a new processing node, a resource can be obtained only from a disk array instead of a high-speed coordinator node. Efficiency is low because a processing node cannot be preheated rapidly.